In this specification where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date, publicly available, known to the public, part of common general knowledge, or otherwise constitutes prior art under the applicable statutory provisions; or is known to be relevant to an attempt to solve any problem with which this specification is concerned.
According to the American Diabetes Association, diabetes is the fifth-deadliest disease in the United States. Since 1987 the death rate due to diabetes has increased by 45 percent. There are an estimated 20.8 million children and adults in the United States, or 7% of the population, who have diabetes. The total annual economic cost of diabetes in 2007 was estimated to be $174 billion. This is an increase of $42 billion since 2002. This 32% increase means the dollar amount has risen over $8 billion each year.
A critical component in managing diabetes is frequent blood glucose monitoring. Currently, a number of systems exist for self-monitoring by the patient. Most fluid analysis systems, such as systems for analyzing a sample of blood for glucose content, comprise multiple separate components such as separate lancing, transport, and quantification portions. These systems are bulky, and often confusing and complicated for the user. The systems require significant user intervention.
Technology in the field of self-monitoring of blood glucose has placed the burden of acquiring sufficient blood for conducting a test on the user of the technology. Earlier versions of consumer-oriented self-monitoring products usually required many microliters of blood.
Lancing devices and the lancets themselves have also evolved somewhat over the past few decades. Some lancing mechanisms may produce relatively less pain by either (1) projecting the lancet in and out of the skin in a more straight path and thus reducing stimulation of percutaneous nerves which provide the pain stimulus; and (2) offering depth control in the lancing device so that the user may balance the expression of sufficient blood against the level of pain. Furthermore, lancet manufacturers offer a variety of lancet sizes, lengths, and tip bevel patterns with some companies claiming that their lancet is less painful than others.
What remains clear is that the most testers, when lancing at the finger, often must put down the lancing device after creating a wound and apply pressure near the finger tip in order to produce sufficient blood for the test strip in the meter. Many instructions for use of conventional meter systems specifically prescribe that the user perform this “milking” process because without it, many will not spontaneously produce the required volume. Applicants have observed this phenomenon in the use of commonly available commercial sampling and meter systems. In one study, when a trained professional lanced the finger tips of 16 volunteer diabetic subjects at the maximum depth setting on commercially available device under controlled conditions, only 15% of lanced sites spontaneously produced sufficient blood for the meter to accurately measure glucose levels.
Conventional sampling devices and methods are overly reliant upon user intervention, such as milking, in order to consistently express a sufficient quantity of blood from the wound site. Thus, it would be advantageous to provide constructions, arrangements and techniques that improved the ability to consistently and spontaneously obtain an adequate sample of body fluid from a sampling site on the skin of the user.